> The combination of these two can be used to generate any of the contextual
> shapes from the nominal shapes for scripts like Arabic and Hebrew, assuming
> your font(s) have all the necessary glyphs.

The trouble is that there's evidence that the Hebrew final forms
aren't used merely contextually. Robert Hetzron's article on
Hebrew in _The World's Major Languages_ (Comrie, ed.; ISBN
0-19-630632-9 hbk, 0-19-506511-5 pbk) states that non-final
PEH is often used to indicate final [p] in non-native words, as
final PEH normally denotes [f].